1. Field of the Invention
The present invention relates to a semiconductor integrated circuit device, and, for example to a semiconductor integrated circuit device that outputs digital data from an internal circuit via a pad to the outside.
2. Related Art
In semiconductor integrated circuit devices such as NAND flash memories, an I/O supply voltage used for data output recently tends to decrease because of reduced power consumption and noise reduction. When the I/O supply voltage decreases, the conductance of the data output circuit may be reduced. For example, when an I/O power supply is switched via a P-type transistor to an I/O pad, a gate-source voltage of the P-type transistor during an ON operation may decrease because of a decrease in the I/O supply voltage. The conductance of the P-type transistor is reduced and then an output slew rate may decrease. That is, a data output rate of the semiconductor integrated circuit device may decrease.